Diamond cutting method and diamond provided by the method

ABSTRACT

Ten of pavilion main facets are formed with reference to the previously formed five of first pavilion main facets in which an initial first main facet is formed in a position centered on a line shifted approximately fifteen degrees from the ridge of the row diamond on the pavilion side. Ten of pavilion main facets  19  radiate from the curette  18  and twenty of lower girdle facets are formed between the adjacent pavilion main facets on the pavilion side of the diamond  1.

BACKGROUND OF THE INVENTION

The present invention relates to a method of cutting diamond forproviding a diamond with a strong brilliance and diamonds obtainedthereby, and more particularly to a method of cutting diamond in whichten, which is considerable number in comparison with conventionaldiamonds, projections of heart and allow are observed under apredetermined lighting condition.

Conventionally, a diamond comprises a generally trapezoidal conic crownhaving a flat table on top, a generally conic pavilion having an acutecurette, and a strip-like girdle provided on the lateral surface alongthe boundary of the crown and the pavilion. A conventional diamond iscommonly cut in order to form a table 81, eight crown main facets 82,eight star facets, and sixteen upper girdle facets 84 on the crown sideand eight pavilion main facets 85 and sixteen lower girdle facets 86 onthe pavilion side by a method called ‘round brilliant cut’ as shown inFIGS. 11 and 12.

For applying a polishing process on the pavilion side by theabove-mentioned method, for example, one of ridges 91 of raw diamond 3in crystal form shown in FIGS. 8(a) and 13(a) is flatten and a firstpavilion main facet 92 centered on the ridge 91 (refer to FIG. 13(b)) isformed as a first step. Subsequently, three other ridges 91 are flattenin a similar manner as mentioned above and four pavilion main facets 92are formed altogether as shown in FIG. 13(c). In the event as mentionedabove, four first pavilion main facets 92 are formed and therefore eachof the central angles 95 of the main facets 92 becomes ninety degrees.Thereafter, the boundary line 93 formed between two adjacent firstpavilion main facets is flatten by polishing and eight pavilion mainfacets 94 centered on the ridges 91 with the central angles of fortyfive degrees are formed as a second step.

On the other hand, in the event of applying a polishing process on thecrown side, a top portion of the row diamond in crystal form is cut offin order to form a flat table 103 thereon as shown in FIGS. 8(b) and14(a). A first crown main facet 104 is formed by polishing a portioncentered on a ridge 101 in the row diamond 3 in crystal form flat andthree other pavilion main facets 104 are formed subsequently, whichtotals to four pavilion main facets as a first step (refer to FIGS.14(b) and 14(c)). In the event as mentioned above, each boundary line105 of two adjacent first crown main facets 104 meets the next boundaryline with an angle 108 of ninety degrees in relation to a center point.Thereafter, eight of second crown main facets 107 having central angles109 of forty-five degrees are formed by polishing portions centered onthe boundary lines 105 as a second step.

Incidentally, a device called tang 54 for holding the row diamond 3 anda scaif 51 formed of a flat steel plate strewed with diamond powder areused in the polishing process as mentioned above. The row diamond 3 isheld by the tang 54 capable of changing the angle at forty-five degreesand polished by the rotating surface of the scaif 51 as shown in FIG.10.

And it is empirically known that a heart and allow phenomenon may beobserved in a diamond in an excellent proportion among the diamondsprocessed as mentioned above by using a magnifying device when one ofthe main facets of the diamond is illuminated by the light coloredthrough a color filter and the remainder are shielded from incidentlight. The heart and allow phenomenon is one of the strongest sellingpoint as a proof of excellence in brilliance of the diamond. When adiamond finished in round brilliant cut is mounted in a face-updirection (having a table of a crown upward) under a predeterminedlighting condition, eight of allow phenomenon 123 projecting over thesurface may be observed as shown in FIG. 15. And when theabove-mentioned diamond is mounted in a face-down direction (having thetable of the crown downward) under a predetermined lighting condition,eight of heart phenomenon 124 projecting over the surface may beobserved as shown in FIG. 16.

Generally diamond is colorless but superior to other jewels in itsbrilliance. And it is understood that the brilliance caused byreflection called ‘brilliancy’, an iris called ‘fire’ for dispersinglight like a prism, and flashes called ‘scintillation’. Therefore,diamonds emitting a stronger brilliance are required.

SUMMARY OF THE INVENTION

In view of the above-mentioned facts, it is therefore an object of thepresent invention to provide a method of cutting diamond capable ofemitting stronger brilliance and showing more heart and allow phenomenonthan conventional diamonds finished in round brilliant cut and diamondsobtained thereby.

That is, a method of cutting diamond of the present invention forproviding a diamond with a generally trapezoidal conic crown having aflat table on top, a generally conic pavilion having an acute curette atthe center, and a strip-like girdle provided on the lateral surfacealong the boundary of the above-mentioned crown and the above-mentionedpavilion is characterized in comprising:

a first step of forming an initial first pavilion main facet centered ona line shifted approximately fifteen degrees from a ridge formed on thepavilion side of a row diamond in crystal form and the remainder of thefirst pavilion main faces subsequently, which totals five of firstpavilion main facets, and

a second step of forming ten of second pavilion main facets centered onthe boundary lines between the above-mentioned first pavilion mainfacets. And a method of cutting diamond of the present invention forproviding a diamond with a generally trapezoidal conic crown having aflat table on top, a generally conic pavilion having an acute curette atthe center, and a strip-like girdle provided on the lateral surfacealong the boundary of the above-mentioned crown and the above-mentionedpavilion is characterized in comprising:

a first step of forming an initial first crown main facet centered on aline shifted approximately fifteen degrees from a ridge formed on thecrown side of the row diamond in crystal form and the remainder of thefirst crown main faces subsequently, which totals five of first crownmain facets, and

a second step of forming ten of second crown main facets centered on theboundary lines between the above-mentioned first crown main facets.

Therefore, the method facilitates the process of forming ten of pavilionmain facets and ten of crown main facets by polishing each facetcentered on a line shifted approximately fifteen degrees from a ridge ofthe row diamond in crystal form while getting clear of portionsdifficult to polish in the row diamond.

The method of cutting diamond of the present invention claimed in claims1 and 2 is characterized in using a device providing means for using atang for changing the direction of the above-mentioned row diamond heldtherein at a predetermined angle and means for applying a polishingprocess with respect to the above-mentioned row diamond by rotating thescaif in the steps of forming the above-mentioned first and the secondpavilion main facets and the above-mentioned first and the second crownmain facets, in which the above-mentioned device applies a polishingprocess with respect to the above-mentioned row diamond by chaining thedirection of the above-mentioned row diamond held therein at an angle ofthirty-six degrees.

Therefore, ten of pavilion main facets and ten of crown main facets maybe formed at a correct angle ratio.

The present invention is characterized in a diamond obtained by thecutting method as claimed in claims 1 through 3. And the diamond of thepresent invention is characterized in providing a generally trapezoidalconic crown having a flat table on top, a generally conic pavilionhaving an acute curette at the center, and a strip-like girdle providedon the lateral surface along the boundary of the above-mentioned crownand the above-mentioned pavilion, in which ten of pavilion main facetsradiating from the above-mentioned curette and twenty of lower girdlefacets formed between adjacent pavilion main facets are formedrespectively on the above-mentioned pavilion side. And the diamond ofthe present invention is characterized in providing a generallytrapezoidal conic crown having a flat table on top, a generally conicpavilion having an acute curette at the center, and a strip-like girdleprovided on the lateral surface along the boundary of theabove-mentioned crown and the above-mentioned pavilion, in which ten ofstar facets encircling the above-mentioned table, ten of crown mainfacets encircling the above-mentioned star facets, and twenty of uppergirdle facets further encircling the above-mentioned crown main facetsare formed on the above-mentioned crown side.

Further, the diamond of the present invention claimed in claims 1through 6 is characterized in that a projection of ten heart shapes areobserved when the above-mentioned diamond is mounted in face-downdirection under a predetermined lighting condition. And the diamond ofthe present invention claimed in claims 1 through 6 is characterized inthat a projection of ten allow shapes are observed when theabove-mentioned diamond is mounted in face-up direction under thepredetermined lighting condition.

Therefore, the diamond of the present invention is capable of embodyingmore heart and allow phenomenon as a proof of excellence of diamonds andemitting stronger brilliance.

It is generally thought that the more pavilion facet on the surface, thestronger a diamond emits brilliance. However, in the event that thepavilion main facets or the crown main facets are formed more thannecessary, each shape in the heart and allow phenomenon which is a proofof excellence in cutting and brilliance gets too close to each other andmay hardly be observed by the unaided eye. And in the event ofincreasing the pavilion main facets by using the conventional cuttingmethod, polishing process may not proceed favorably in relation to therow diamond in crystal form. From a assiduous study of problemsmentioned above, the inventor of the present invention accomplished thepresent invention for cutting diamond in which the pavilion main facetsand the crown main facets are increased as many as possible to theextent that the heart and allow phenomenon may be observed by theunaided eye.

It is therefore an object of the present invention to provide a diamondin which an initial first main facet is formed in a position centered ona line shifted approximately fifteen degrees from a ridge formed on therow diamond in crystal form and the remainder of the first main facetsare formed subsequently, which totals five of first pavilion mainfacets, and therearter ten of second main facets centered on theboundary lines between the adjacent first main facets are formed on bothpavilion side and crown side, thereby allowing the diamond to emitstronger brilliance and embody the heart and allow phenomenon observedby the unaided eye.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view for showing a diamond of a first embodiment ofthe present invention,

FIG. 2 is a plan view for showing the diamond viewed from a crown sideof the first embodiment of the present invention,

FIG. 3 is a plan view for showing the diamond viewed from a pavilionside of the first embodiment of the present invention,

FIG. 4 is a plan view for showing allow phenomenon in the diamond of thefirst embodiment of the present invention,

FIG. 5 is a plan view for showing heart phenomenon in the diamond of thefirst embodiment of the present invention,

FIGS. 6(a) through 6(d) are drawings for illustrating steps of a methodof cutting diamond of the first embodiment of the present invention onthe pavilion side,

FIGS. 7(a) through 7(d) are drawings for illustrating steps of themethod of cutting diamond of the first embodiment of the presentinvention on the crown side,

FIGS. 8(a) and 8(b) are perspective views for showing a diamond incrystal form and the same in the state of being cut at its top edge,

FIG. 9 is a drawing for showing growth lines of the diamond in crystalform,

FIG. 10 is a drawing for showing a device used in the method of cuttingdiamond of the first embodiment of the present invention,

FIG. 11 is a plan view for showing a conventional diamond viewed fromthe crown side,

FIG. 12 is a plan view for showing a conventional diamond viewed fromthe pavilion side,

FIGS. 13(a) through 13(d) are drawings for illustrating steps of amethod of cutting the conventional diamond,

FIGS. 13(a) through 13(d) are drawings for illustrating steps of themethod of cutting the conventional diamond on the pavilion side,

FIGS. 14(a) through 14(d) are drawings for illustrating steps of themethod of cutting the conventional diamond on the crown side,

FIG. 15 is a plan view for showing the allow phenomenon in theconventional diamond, and

FIG. 16 is a plan view for showing the heart phenomenon in theconventional diamond.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, preferred embodiments of the presentinvention are described more particularly. FIG. 1 is a front view forshowing a diamond of a first embodiment of the present invention. FIG. 2is a plan view for showing the diamond viewed from a crown side of thefirst embodiment of the present invention. And FIG. 3 is a plan view forshowing the diamond viewed from a pavilion side of the first embodimentof the present invention.

A diamond 1 has a generally trapezoidal conic crown 11 (generallytrapezoidal in cross section), a generally conic pavilion 12 (generallytriangle in cross section), and a strip-like girdle provided on thelateral surface along the boundary of the crown 11 and the pavilion 12as shown in FIG. 1.

A flat table 14 is formed in the center of the crown 11 of the diamond 1as shown in FIG. 2. Ten of star facets 15 are formed around the table14. And generally rhombic crown main facets 16 (usually called ‘bezelfacet’) are formed encircling the star facets 15. Further, twenty ofupper girdle facets 17 are formed in contact with outer sides of thecrown main facets 16.

Ten of pavilion main facets 19 radiating from an acute curette 18 areformed in the pavilion 12 of the diamond 1 as shown in FIG. 3, Andtwenty of lower girdle facets are formed between adjacent pavilion mainfacets.

Ten of heart and allow phenomenon are observed in the diamond 1 in anexcellent proportion of the present invention. When the diamond 1 ismounted in a face-up direction (directing the table 14 upward), ten ofheart and allow phenomenon 21 may be observed as shown in FIG. 4 andwhen the diamond 1 is mounted in a face-down direction (directing thetable 14 downward), ten of heart and allow phenomenon 22 may be observedas shown in FIG. 5 by using a magnifying device on condition that one ofthe main facets is illuminated by light colored through a color filterwhile the remainder are shielded from incident light.

The diamond 1 of the present invention has ten of pavilion main facets19. Brilliancy (reflection) of a diamond is created by the light(represented as an allow in FIG. 1) coming in through the crown 11 side,reflecting at the pavilion main facets 19, and going out through thecrown 11 side as shown in FIG. 1. Therefore, the diamond 1 of thepresent invention providing more pavilion main facets 19 is capable ofemitting brilliance stronger than conventional diamonds finished inround brilliant cut. Additionally, diffused light and sparkle are causedwhen reflection passes and refracted at the crown main facets 16.Therefore, the diamond 1 of the present invention providing more crownmain facets 16 is capable of emitting brilliance stronger thanconventional diamonds.

And in the diamond 1 of the present invention, ten of crown main facets16 and ten of pavilion main facets 19 are formed as mentioned above andtherefore ten heart and allow phenomenon which is more than conventionaldiamond in round brilliant cut may be observed. The number of ten hasbeen thought to have meanings of ‘perfection’ or ‘development’ from ofold in Europe and America, which is an important selling point for anornamental piece. Thus, value of the diamond is enhanced by embodyingten of hearts and allows.

Next, the method of cutting diamond of the present invention isdescribed. FIGS. 6(a) through 6(d) are drawings for illustrating anembodiment of the method of cutting the diamond of the present inventionon the pavilion side and FIGS. 7(a) through 7(d) are drawings forillustrating an embodiment of the method of cutting the diamond of thepresent invention on the crown side. FIGS. 8(a) and 8(b) are perspectiveviews for showing a diamond in crystal form and the same in the state ofbeing cut at its top edge. And FIG. 9 is a drawing for showing growthlines of the diamond in crystal form.

In the event of polishing surfaces on the pavilion side, a firstpavilion main facet 25 a is formed initially on a center line 24 shiftedapproximately fifteen degrees 27 from a ridge 23 formed on the pavilionside of a row diamond 3 in crystal form (FIG. 6(b)) and the remainingfirst pavilion main facets 25 are formed subsequently (FIG. 6(c)) as afirst step. In the above-mentioned event, five of first pavilion mainfacets are formed in total and therefore the central angle 29 of eachfirst pavilion main facet becomes seventy-two degrees. And ten of secondpavilion main facets 32 providing central angles 30 at thirty-sixdegrees are formed in positions centered on boundary lines 31 betweenadjacent first pavilion main facets 25 as a second step.

In the method of the present invention, the point of applying thepolishing process on the position centered on the center line 24 shiftedapproximately fifteen degrees from the ridge 23 of the diamond incrystal form relates to growth lines in the row diamond 3 in crystalform. A diamond has ridges X, Y and growth lines 33 as shown in FIG. 9.In the event of dividing both of ridges X and Y into four parts by thegrowth lines 33, a position on a line Z (a line shifted from the ridge Xat an angle 34 of twenty-two point five degrees) is the most difficultportion to polish flat. Therefore, in the steps of forming the firstpavilion main facets 25 and the second pavilion main facets 32, thecenter lines of the above-mentioned facets are preferably kept fromoverlapping with the line Z or the facets are hardly formed flat andhardly polished properly.

In a conventional round brilliant cut, four of first pavilion mainfacets are formed in the positions centered on four ridges of the rowdiamond 3 as a first step. Thereafter, the second pavilion main facetsare formed in the positions centered on the boundary lines betweenadjacent first pavilion main facets. Thus, the line Z kept fromoverlapping with the center lines of the facets and eight of secondpavilion main facets are formed properly.

However, in the event of forming ten of the pavilion main facets by theconventional method, one or more of the center lines of the pavilionmain facet overlap with the line Z. Accordingly, the center line of theinitial first pavilion main facet 25 is shifted from the ridge 23 at anangle 27 of approximately fifteen degrees in the first step in order toprocess all the pavilion main facets properly.

And FIGS. 7(a) through 7(d) are drawings for illustrating an embodimentof the method of cutting the diamond of the present invention on thecrown side.

In the event of processing the crown side, a flat table 3 is formedafter an edge portion of the diamond in crystal form is cut off as shownin FIG. 8 (b). And an initial first crown main facet 44 a is formed(Fig. (b)) in position centered on a line 47 shifted approximatelyfifteen degrees from a ridge 41 of the diamond 3 in crystal form shownin FIG. 7(a) and the remaining first crown main facets 44 are formedsubsequently (FIG. 7(c)) as a first step. In the above-mentioned event,five of the first crown main facets 44 are formed in total and one ofcentral angles 49 formed between two adjacent boundary lines 45 whichmeet at the center becomes seventy-two degrees consequently. Thereafter,ten of second crown main facets 48 are formed by polishing the positionscentered on the boundary lines 45 between the adjacent first crown mainfacets 44 as a second step. The central angle 50 in the above-mentionedstep becomes thirty-six degrees.

The polishing process characterized in providing a standard line 24shifted approximately fifteen degrees from the ridge 23 of the diamondin crystal form is applied in a similar manner to the above-mentionedcutting method of forming the pavilion facets in the diamond of thepresent invention and is ascribable to the position of the growth linesin the row diamond in crystal form.

Additionally, after forming the pavilion main facets and the crown mainfacets, narrower surfaces of lower girdle facets, star facets and uppergirdle facets are formed with reference thereto.

A device shown in FIG. 10 is used for applying the polishing process forforming facets to the diamond A numeral 51 indicates a base usuallycalled scaif is used in the polishing process, The scaif 51 is rotatablyheld by a shaft 52. And an upper surface of the scaif 51 is coated withdiamond powder 53 as polishing powder by using oil and the like.

Rotational frequency (speed) of the shaft 52 is controlled by a rotationcontrol portion which is not shown in the drawing. A control portion 55is provided above the scaif 51 and a holding shaft having a holdingportion 56 which is usually called tang 54 for holding the row diamond 3is provided as an edge of the control portion 55.

The control portion 55 comprising a movable lifting means not shown inthe drawings controls descent and ascent of the shaft to start and tostop applying the polishing process to the row diamond 3. Additionally,the control portion 55 controls the angle, the length of processing timeand polishing pressure of the tang 54 in order to form facets on thediamond. Incidentally, the device is capable of applying the polishingprocess to the row diamond 3 with the tang holding the diamond 3changing the angle at thirty-six degrees.

In the polishing device having the above-mentioned construction, thescaif 51 is rotated by the shaft 52 at a predetermined rotationalfrequency, the row diamond 3 is held by the tang 54 at its crown side,the holding shaft is controlled to descend by the control portion 55,and thereafter the pavilion side of the diamond is polished in contactwith the scaif 51. In the above-mentioned event, the angle of the tang54 shifted at approximately thirty-six degrees and the length of timeand the pressure of polishing are controlled by the control portion 55.And the initial first main facet 25 a is formed by polishing a positioncentered on a line 24 shifted approximately fifteen degrees from theridge 23 of the row diamond in crystal form and the remainder of thefirst main facets 25 are formed subsequently, which totals five of firstpavilion main facets. Thereafter, ten of second pavilion main facets 32centered on the boundary lines 31 between the adjacent first main facets25 are formed.

The method of polishing the crown main facets on the diamond of thepresent invention is performed in a generally similar manner to theabove-mentioned method of polishing the pavilion main facets.

Further, after forming the pavilion main facets and the crown mainfacets are formed, lower girdle facets, star facets and upper girdlefacets that are narrower in width are formed in a generally similarmanner to the conventional method of cutting a diamond.

Incidentally, including the above-mentioned steps in the method ofcutting diamond usually called blocking, other steps of marking, sawing,bruting, table polishing and the like are performed in the similarmanner to the conventional cutting process.

Too many pavilion main facets and crown main facets cause difficulty inobserving the heart and allow phenomenon as the proof of excellence incutting and brilliance by the unaided eye, even though the facets areeffective to emit stronger brilliance. Therefore, the number of thepavilion main facets and of the heart and allow phenomenon is preferablyaround ten. And in the process of polishing the first main facet, theangle of the center line shifted from the ridge 23 of the row diamond 3in crystal form is preferably fifteen degrees as mentioned above.However, any angle is possible within limits acceptable in the polishingprocess.

Thus, as the diamond obtained by the methods of the present inventionhas ten of pavilion main facets and ten of crown main facets, theincident light is reflected more brightly in the pavilion, refracted inthe crown and sent out. Accordingly, more heart and allow phenomenonthat is a proof of excellent cutting and brilliance may be observed bythe unaided eye, and the above-mentioned diamond can emit brilliancestronger than the conventional diamond.

Further, with the method of cutting diamond of the present invention, adiamond providing ten of pavilion main facets and ten of crown mainfacets may be obtained easily and accurately And those skilled in theart will recognize that the invention can be practiced with modificationwithin the spirit and scope of the appended claims. A diamond is namedas an example in the above-mentioned embodiment and the presentinvention may be applied to other jewels.

As it has been described as above, the present invention ischaracterized in forming the initial first main facet in the positioncentered on the line shifted approximately fifteen degrees from theridge of the row diamond in crystal form and five of the first mainfacets in total, and in forming ten of second main facets referring tothe boundary lines between the adjacent first main facets. And theabove-mentioned main facets are formed on both of the crown and thepavilion sides easily and accurately. Therefore, the present inventioncan provide a diamond capable of embodying more heart and allowphenomenon that is a proof of excellent cutting and brilliance as far asit may be observed by the unaided eye, thereby emitting strongerbrilliance.

1. A method of cutting diamond for providing a diamond with a generallytrapezoidal conic crown having a flat table on top, a generally conicpavilion having an acute curette at the center, and a strip-like girdleprovided on the lateral surface along the boundary of said crown andsaid pavilion comprising: a first step of forming an initial firstpavilion main facet centered on a line shifted approximately fifteendegrees from a ridge formed on the pavilion side of a row diamond incrystal form and the remaining first pavilion main faces subsequently,which totals five of first pavilion main facets, and a second step offorming ten of second pavilion main facets centered on the boundarylines between said first pavilion main facets.
 2. A method of cuttingdiamond for providing a diamond with a generally trapezoidal conic crownhaving a flat table on top, a generally conic pavilion having an acutecurette at the center, and a strip-like girdle provided on the lateralsurface along the boundary of said crown and said pavilion comprising: afirst step of forming an initial first crown main facet centered on aline shifted approximately fifteen degrees from a ridge formed on thecrown side of a row diamond in crystal form and the remaining firstcrown main faces subsequently, which totals five of first crown mainfacets, and a second step of forming ten of second crown main facetscentered on the boundary lines between said first crown main facets. 3.A method of cutting diamond as claimed in claim 1, further comprisingthe step of: using a device providing means for using a tang forchanging the direction of said row diamond held therein at apredetermined angle and means for applying a polishing process to saidrow diamond by rotating the scaif in the steps of forming said first andsaid second pavilion main facets, in which said device applies apolishing process to said row diamond by changing the direction of saidrow diamond held therein at an angle of thirty-six degrees.
 4. A diamondobtained by the cutting method as claimed in claim
 1. 5. A diamondobtained by the cutting method as claimed in claim 1, comprising: ten ofpavilion main facets radiating from said curette and twenty of lowergirdle facets formed between adjacent pavilion main facets formedrespectively on said pavilion side.
 6. A diamond obtained by the cuttingmethod as claimed in claim 2, comprising: ten of star facets encirclingsaid table, ten of crown main facets encircling said star facets, andtwenty of upper girdle facets encircling said crown main facets formedon said crown side.
 7. A diamond obtained by the cutting method asclaimed in claim 1, wherein a projection of ten heart shapes areobserved when said diamond is mounted in face-down direction under apredetermined lighting condition.
 8. A diamond obtained by the cuttingmethod as claimed in claim 1, wherein a projection of ten allow shapesare observed when said diamond is mounted in face-up direction under thepredetermined lighting condition.
 9. A method of cutting diamondaccording to claim 2, further comprising the step of: using a deviceproviding means for using a tang for changing the direction of said rowdiamond held therein at a predetermined angle and means for applying apolishing process to said row diamond by rotating the scaif in the stepsof forming said first and said second crown main facets, in which saiddevice applies a polishing process to said row diamond by changing thedirection of said row diamond held therein at an angle of thirty-sixdegrees.
 10. A diamond obtained by the cutting method according to claim2.
 11. A diamond obtained by the cutting method according to claim 3.12. A diamond obtained by the cutting method according to claim 2,wherein a projection of ten heart shapes are observed when said diamondis mounted in face-down direction under a predetermined lightingcondition.
 13. A diamond obtained by the cutting method according toclaim 3, wherein a projection of ten heart shapes are observed when saiddiamond is mounted in face-down direction under a predetermined lightingcondition.
 14. A diamond obtained by the cutting method according toclaim 5, wherein a projection of ten heart shapes are observed when saiddiamond is mounted in face-down direction under a predetermined lightingcondition.
 15. A diamond obtained by the cutting method according toclaim 6, wherein a projection of ten heart shapes are observed when saiddiamond is mounted in face-down direction under a predetermined lightingcondition.
 16. A diamond obtained by the cutting method according toclaim 2, wherein a projection of ten allow shapes are observed when saiddiamond is mounted in face-up direction under the predetermined lightingcondition.
 17. A diamond obtained by the cutting method as claimed inclaim 3, wherein a projection of ten allow shapes are observed when saiddiamond is mounted in face-up direction under the predetermined lightingcondition.
 18. A diamond obtained by the cutting method according toclaim 5, wherein a projection of ten allow shapes are observed when saiddiamond is mounted in face-up direction under the predetermined lightingcondition.
 19. A diamond obtained by the cutting method according toclaim 6, wherein a projection of ten allow shapes are observed when saiddiamond is mounted in face-up direction under the predetermined lightingcondition.